1. Field of the Invention
This invention relates generally to dough sheeters, and more particularly to those employed for rolling dough for use in baking pizzas.
2. Description of the Prior Art
Apparatus for rolling or sheeting dough for various end products has been provided in many forms, such as that for sheeting dough for pizza skins disclosed in U.S. Pat. No. 4,255,106. A problem encountered in the subsequent baking of the pizzas is "blistering" of the skins, namely, irregular upward movement or expansion of portions thereof from the supporting pans, which results in scorching or burning of the cheese and other ingredients that have been placed thereon.
In individual assembly for baking of pizzas, perforation of the skins has been attempted by first manually moving a spiked roller over the skins on the baking pans. While that was not completely satisfactory due to the nature of the dough which, because of its "memory," tends to close such perforations and form a thin membrane across their lower ends which does not prevent blistering during baking, the latter was aborted by the baker reaching into the oven and with a stick, or the like, manually breaking or knocking down any resulting blisters.
However, the expanding use of high speed conveyor-type ovens, now deemed essential in fast-food retail operations and in commercial production of pizzas as shelf items, prevents such selective manual breaking of forming blisters and, therefore, requires some new method and apparatus for insuring against the forming of any dough blisters. Recognizing this, attempts have been made to effectively and completely perforate the sheeted dough by incorporating an axially aligned and spaced gang of star wheels in a dough sheeter, such as that of U.S. Pat. No. 4,255,106, for cooperation with the lowermost dough roller therein. Those attempts have failed because of the difficulty of maintaining accurate alignment and engagement of the individual star wheels with their backup roller and despite the use of a separate backup roller and different materials therefor.